Preparation of a bioactive cochlea implant electrode by electrophoretic deposition of DNA-functionalized nanoparticles

• Applicants: Professor Dr. Matthias Epple; Dr. Stefan Hansen
• Subject Area: Otolaryngology, Phoniatrics and Audiology
• Term: from 2016 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 328855289

So far, no study on the coating of a Cochlea-Implant electrode with DNA-transfecting nanoparticles has been performed. In this project, an electrode shall be coated with nanoparticles that carry DNA encoding for the proteins NT-3 and BDNF and studied in vitro. A surface-mediated transfection will lead to a release of NT-3 and BDNF into the surrounding tissue. This will enhance the growth of neurites towards the electrode and improve the hearing ability of the patient. For this, the physical, chemical and biological properties of the nanoparticles (especially transfection efficiency and cytotoxicity) shall be studied. Thereafter, the DNA-functionalized nanoparticles will be deposited by electrophoretic deposition in different layers on the substrate. The efficiency of the surface-mediated transfection from different layers (sequential release of nanoparticles) will be studied. The goal is the investigation of the deposited functionalized nanoparticles in a spiral ganglial cell culture. As spiral ganglia cells are finally differentiated cells, they will be obtained from neonatal mouse cochlea and studied in a dissociated cell culture. It will be determined whether the transfection with NT-3 and BDNF is successful. Finally, cultures of spiral ganglia explants will be prepared. They will be co-cultured on a nanoparticle-coated Cochlea-Implant electrode. It will be investigated whether the growth of neurites towards the functionalized electrode is enhanced. Especially important are the neurite growth behavior and the interaction of neurites with Schwann cells as promotors of regeneration.

• DFG Programme: Research Grants